Suction apparatus for paper-machines.



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E T A R G U .M n,... R .L 3 4u. 2 n0 7 0l SUGTION APPARATUS FOR PAPER MACHINES.

` APPLICATION FILED JUNE 11, 1903.

.'No MODEL.

' SWS/Wut PATENTED JUNE 14, 1904'.

P. c. MGGRATE -sUGTIoN APPARATUS PoR PAPER MACHINES.

- APPLICATION FILED JUNE 11, 1903.

2 SHEETS-SHEET 2.

NO MDBL.

UNITED STATES- -lzatented June 14, 1904.

PATENT OFFICE.

SUCTION APPARATUS FOR PAPER-MACHINES.

SPECIFICATION forming part of Letters Patent No. 762,431, dated June 14, 1904.

Application ned rune 11,1903. serial No. 161,065. No moda.;

T0 all whom, t may concern.'

Be it known that I, PATRICK O. MGGRATH, a citizen of the United States, residing at Glens Falls, in the county Aof Varren and State of New York, have invented certain new and useful Improvements in Suction Apparatus for Paper-Machines; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in the suction mechanism of paper-making machines of the Fourdrinier class, inwhich the saturated pulp to be made into paper is carried by a traveling endless screen or apron over suction devices which extract the surplus moisture from the pulp prior to the feed of the latter to the paper-forming rolls.- These suction devices as ordinarily constructed consist of stationary boxes having perforated tops over which the screen passes, the said boxes being connected to suction-pumps which draw the screen down upon theboxes and extract the water from the pulp through the said perforated tops of the boxes. One objection to suction devices of this character is the limited suction capacity afforded, owing to the small perforated surface of the boxes, whereby as a result of the rapid travel of the screen insufcient extraction of the water from the pulp frequently occurs. Another objection is that the frietional sliding contact of the screen over the perforated tops of the boxes causes injury to both and rapid destruction of the screen, which must be replaced at intervals at comparatively great expense.

The object of the present invention is to provide suction mechanism which is simple, durable, and efficient and which, while yielding a greater suction area, will operate without injury either to the boxes or apron.

I/Vith this and other objects subordinate thereto in view lthe invention consists of certain novel features of construction, combination, and arrangement of parts, as will behereinafter Inore fully described, and particularly pointed out in the appended claims.

In the accompanying drawings, Figure 1 is a perspective view showing the application of the invention, parts being broken away to expose the construction. Fig. 2 is a perspective view of the main suction-box, a portion of the top thereof being broken away to show the interior valves. Fig. 3 is a similar view of one of the suction-boxes of the endless rotary suction devices. Figs. 4, 5, and 6 are detail views showing modifications in the construction of the endless perforated belt. Fig. 7 is a detail section showing the adjustable connection between the suction-box and one of its supporting-brackets, and Fig. 8 is a detail cross-sectional view through one of the valves.

In the accom panying drawings I have shown so much of aFourdrinier paper-machine as is .necessary to illustrate the application of my invention, and therein l represents asuitable supporting-frame having bearings 2 for the shafts of drums 3 and 4, which are disposed transversely and around which travels the endless gauze screen or apron 5, which conveys the paper-pulp from a suitable hopper to the couch or paper-forming rolls. (N ot shown.) The shaft of the drum 4 is provided with a drive-pulley 4', adapted to receive motion from a band or belt driven from any suitable source of power.

Arranged below the screen 5 is a main suetion-box 6, to which are connected suctionpipes 7, which in practice are designed to conneet the box with one or more suction-pumps in the usual way. rIhe box 6 is supported upon the frame l by brackets 8, each of which is provided with an elongated vertical slot 9, receiving a bolt or similar fastening connection IO, whereby the suction-box is ad j ustabl y secured upon the brackets, so that it may be raised and lowered to dispose it at the proper distance below the upper or working stretch of the endless apron 5. The box 6 is provided with a cover l1, having a detachable central portion 12 and end flanges 13, the cover as thus constructed being made of wood or metal, as preferred. The central portion l2 thereof expelled.

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within the suction-box, at the sides or ends thereof, below the perforated central top porl tion 12, and are adjustable by means of screwshafts 16 and hand-wheels 17 to cover one or more of the end slots of the series 14 to close said slots and throw them out of action, thereby adapting the suction box for use in the manufacture of different widths of paper. Each of the said valves 15 comprises a box or casing 15, which is provided with a top wearplate 18, which contacts directly with the under surface of the part 12 and is guided in the box 15 by depending guide-flanges 15" and pressed outward by pressuresprings 15", whereby it is adjustable to compensate for wear.

' The ends or lianges'13 of the top of the main Suction-box 6 are bent downward or deflected, and cooperating' with said box is an endless perforated belt or apron 19, consisting of a series of parallelly-arranged auxiliary suction-boxes 20, which are of greater length than the width of the box 6 and are connected at their ends by series of links 21, the said links forming two endless side chains, which run over and around sprocket-wheels 22, fixed upon the shafts of drums 23. The said shafts of these drums 23 are journaled in bearingbrackets 24, supported upon the frame 1, and the drums are disposed transversely of the frame at opposite ends of the main suctionbox 6, the belt or apron 19 passing around the said drums, thence over the top 11 of the suction-box 12 and below/the upper stretch of the screen 5, andbeneath the box between the same and the lower stretch of the screen 5. For the purpose of adjusting' the belt 19 to take up any slack therein the brackets 24 of one of the drums 23 are provided with slots 25 for the passage of screws 26, entering the frame 1, and are further provided with adjusting-screws 27, by means of which when the screws 26 are loosened the said brackets may be adjusted longitudinally on and off the frame to increase or diminish the tension ofthe belt, as desired.

The auxiliary suction-boxes 2O are provided with apertures 28, affording communication between the working surface of the screen 5 and the suction-box 6, and they may further be provided with perforated tops 29, consisting of gauze or foraminous plates, as shown in Fig. 3, or all the boxes of the belt 19 may be covered by a belt of gauze 29, as shown in Fig. 1, such belting acting as a common top or cover for all the said suction-boxes 20. In either case the perforated tops or covers of the boxes 2O serve as supports for the working stretch of the screen 5 to prevent the latter from being deflected downwardly to too great an extent under the suction action produced by the exhaust-pumps.

I may make the suction devices 2O of box form, as shown particularly in Figs. 1 and 3, or I may construct them in the form of wooden or metallic strips 20', having, as shown in Fig. 4, longitudinal grooves e intersected by crossgrooves and provided with air-passages c. I may also make the suction devices in the form of strips 20", having, as shown in Fig. 5, conical or pyramidal openings c', and, as shown in said figure, I may construct the strips at their opposite ends with alternating projections Z and recesses d', the projections andrecesses of the adjoining strips throughout the series being adapted to interlock when supported by the cover 11 of the suction-box 6, thus forming a level perforated traveling platform between the cover or platform 11 and the working stretch of the screen 5. The slats or strips 2O*L are preferably made of metal, and the interlitting portions CZ d are machinedressed to fit snugly yet easily and -break joint, so that should the belt wear between the slats the latter will still lit close enough together to prevent any break in the vacuum. It will be observed that the openings c are in independent rows, so that one or more rows may be closed by each valve 15. I may also, as shown in Fig. 6` modify the construction further by mounting the strips or boxes upon transverse cleats or slats e, connected to sprocket-chains 21, the said slats being adapted to traverse guides e to prevent the suetion-boxes or strips from sagging or working out of line during the course of travel of the belt 19. It will be observed that the sides of the suction devices 20 or 20 are provided with packing-strips 30, of rubber, wood, or other suitable material. These strips contact when the suction devices travel over the platform 11 to form the working stretch of the belt 19, thus preventing too much inward movement of said suction devices and adapting them to come nearly into alining parallel position, so as to form a level working stretch designed to conform closely to the Linder surface of the working stretch of the traveling screen 5.

One of the drums 23 is connected through a train of gears 31 with the shaft of the drum L1, so as to communicate motion to the belt 19. Preferably these gears are so proportioned and arranged that the upper stretch of the belt 19 will travel at the same rate of speed as the belt 5, thus preventing any frictional engagement between them, and thus preventing wear on either belt.

In the operation of the invention it will be understood that the screen is supplied with paper-pulp at one end -and conveys the same over the suction mechanism and finally, in practice, conveys the pulp from which the surplus moisture has been extracted to the couch o1' paper-forming rolls. As the belt 5 travels along the belt 19 travels with it, and the working surfaces thereof are in intimate contact above the top or platform portion 11 of the suction-box 6, the suction produced serving to draw the parts down in intimate contact with one another, so that the surplus moisture will IOL) lIO

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be effectively extracted from the pulp. By the downward deflection of the end portion or flanges 13 of the top 11 of the main suctionboxes 6 the advantage is attained that no suction upon the screen 5 is caused at the ends of the suction-boxes l, by which all tendency of the suction mechanism to draw the screen out of line is avoided. It will be apparent that by the use of the traveling suction device 19 in place of the ordinary stationary boxes with which the screen usually contacts two important advantages are obtained, to wit: First, the area of continuous suction-surface is increased, thus enhancing the efHciency of the suction mechanism and producing a more thorough extraction of the water from the saturated pulp, and, second, that as the movable suction device travels with the belt the friction ordinarily produced upon the latter is avoided. Hence little or no wear falls upon either the suction mechanism or the screen, and the cost of maintenance of the machine is accordingly decreased to a considerable extent.

From the foregoing description, taken in connection with the accompanying drawings, the construction and operation of the invention will be readily understood without requiring a more extended explanation.

Various changes in the form, proportion, and the minor details of construction may be resorted to without departing from the principle or sacrificing any of the advantages of this invention.

It will of course be understood that the invention is susceptible of general use as a moisture-extractor. Hence I do not desire to limit it to -the particular kind of constructio of machine herein shown or described.

Having thus fully described my invention, what I claim as new, and desire to secure b v Letters Patent, isW

l. The combination with a supportingframe, and a traveling screen, of a main suction-box below the screen, an endless belt adapted to travel between the box and screen and comprising a series of parallel linked auxiliary suction-boxes, perforated tops for said boxes forming a supporting-surface for the screen, means for adjusting the main suction-box and working portion of the endless belt relative to the working surface of the screen, means for varying the tension of the endless belt, and means for varying the working surface of the suction-box to suit the conditions in making different widths of paper, substantially as described.

2. In an apparatus of the character described, a suction-box, provided with a series of air passages or openings, valves for governing certain of such passages to vary the width of the acting surface of the box, and means for adjusting said valves, substantially as set forth.

3. In an apparatus of the character described, a suction-box provided with a series of air passages or openings, valves therein, means for adjusting the valves to regulate the acting area of said openings, and adjustable wear-plates carried by said valves, substantially as described.

4. In an apparatus of thecharacter described, a suction-box, provided with a removable cover having openings'therein, downwardly bent or deliected end flanges, valves within the box and below the cover, and means for adjusting said valves to govern said openings, substantially as set forth.

5. The combination with atraveling screen,

of a suction-box below the same, and a continuous perforated belt adapted to travel between the box and screen, said belt comprising a series of parallel linked suction devices .provided with openings affording communication between the screen and suction-box, said suction devices being provided with cushioning-strips` upon their sides to limit their inward movement toward one another and to adapt them to extend in straight parallel relation in traveling across the top of the suction-box, substantially as described.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

PATRICK C. MCGRATH. Witnesses:

CHAs. H. CARSON, FLORENCE A. NEWBERRY. 

